There is a lack of theoretical integration and comparative analyses of diaspora nationalist movements. In this article I compare the structures of the diaspora Hindutva and Khalistan movements in the United States, the United Kingdom and Canada. Differences in their mobilizing structures are the result of underlying ideology and strategic choices, rather than political opportunities. The Hindutva movement's use of brokerage contrasts with the Khalistan movement's reliance on gurdwara politics. In understanding mobilizing structure, greater attention should be paid to strategic choices and internal mechanisms instead of focusing solely on the external environment.